Cleanup

src/Dodge/Tree/GenerateStructure.hs

@@ -3,43 +3,47 @@ Procedural generation of tree structures.
 
 A /trunk/ refers to the successive first nodes in lists of children.
 -}
-module Dodge.Tree.GenerateStructure
-    where
-import RandomHelp
-import Control.Monad
+module Dodge.Tree.GenerateStructure where
 
+import Control.Monad
 import Data.Tree
+import RandomHelp
+
 {- Single branched tree (a trunk).  -}
 treePath :: Int -> Tree ()
 treePath 0 = Node () []
-treePath x = Node () [treePath (x-1)]
+treePath x = Node () [treePath (x -1)]
 
 {- Adds a branch at a certain point down a trunk.  -}
-addBranchAt 
-    :: Int      -- ^ Depth to add branch at
-    -> Tree ()  -- ^ Branch to add
-    -> Tree ()  -- ^ Starting tree
-    -> Tree ()
+addBranchAt ::
+    -- | Depth to add branch at
+    Int ->
+    -- | Branch to add
+    Tree () ->
+    -- | Starting tree
+    Tree () ->
+    Tree ()
 addBranchAt 0 b (Node () xs) = Node () (xs ++ [b])
-addBranchAt i b (Node () (x:xs))
-    = Node () (addBranchAt (i-1) b x : xs)
+addBranchAt i b (Node () (x : xs)) =
+    Node () (addBranchAt (i -1) b x : xs)
 addBranchAt _ _ _ = error "Trying to add a branch too far along a tree"
 
 {- Randomly generate a tree containing a maximum of three nodes.  -}
 smallBranch :: RandomGen g => State g (Tree ())
-smallBranch = takeOne
-    [ treePath 0
-    , treePath 1
-    , treePath 2
-    , addBranchAt 0 (treePath 0) (treePath 1)
-    ]
+smallBranch =
+    takeOne
+        [ treePath 0
+        , treePath 1
+        , treePath 2
+        , addBranchAt 0 (treePath 0) (treePath 1)
+        ]
 
 {- Randomly generate a small tree.  -}
 aTreeStrut :: RandomGen g => State g (Tree ())
 aTreeStrut = do
-    d <- state $ randomR (9,11:: Int)
-    nbs <- state $ randomR (2,4)
+    d <- state $ randomR (9, 11 :: Int)
+    nbs <- state $ randomR (2, 4)
     bds <- takeN nbs [1 .. d - 1]
-    bs  <- replicateM nbs smallBranch
+    bs <- replicateM nbs smallBranch
     let trunk = treePath d
     return $ foldr (uncurry addBranchAt) trunk $ zip bds bs